Aedes Mosquitoes
Aedes Mosquitoes
Introduction :
The risk of contracting dengue infection has increased dramatically since the 1940s. This upward trend is due to increases in long-distance travel, population growth and urbanization, lack of sanitation, ineffective mosquito control, and increases in the surveillance and official reporting of dengue cases. Dengue has spread through Southeast Asia, the Pacific Island countries, and the Middle East. Today, approximately 40% of people live in regions of the world where there is a risk of contracting dengue. Dengue is an endemic disease, which means that it occurs regularly, in tropical regions of the world. The disease is endemic in more than one hundred countries in Africa, the Americas, Asia, the Caribbean, and the Pacific. How does dengue spread, and how is this disease transmitted to humans

How Does It Spread:
The dengue virus is transmitted to humans via the bite of an infected mosquito. Only a few mosquito species are vectors for the dengue virus. What is a vector? A vector is a vehicle that carries and transmits a disease to its host organism. Vectors include animals and microorganisms that transmit different diseases. The most common vectors are arthropods, which are invertebrate animals with an external skeleton called an exoskeleton. Arthropods include mosquitoes, ticks, lice, flies, and fleas. For instance, ticks can carry Lyme disease, and some mosquitoes can carry yellow fever, malaria, and dengue fever. When a mosquito bites a person who has dengue virus in his or her blood, the mosquito becomes infected with the dengue virus. An infected mosquito can later transmit that virus to healthy people by biting them. Dengue cannot be spread directly from one person to another, and mosquitoes are necessary for transmission of the dengue virus.

Can any type of mosquito carry dengue. The dengue virus is carried and spread by mosquitoes in the genus Aedes, which includes a number of mosquito species. Of these species, the primary vector of the dengue virus is the species Aedes aegypti. It is the principal dengue vector responsible for dengue transmission and dengue epidemics. Other mosquito species in the genus Aedes — including Aedes albopictusAedes polynesiensis, and Aedes scutellaris — have a limited ability to serve as dengue vectors.

Aedes aegypti
 is a small, dark mosquito that can be identified by the white bands on its legs and a silver-white pattern of scales on its body that looks like an ancient Greek musical instrument called a lyre (Figure 1). Where are these mosquitoes found? Aedes aegypti dwell in tropical and subtropical regions all over the world, mainly between the latitudes of 35°N and 35°S where the winter temperature is no colder than 10°C. Although some mosquitoes may travel farther north or south of these latitudes, they are unable to survive cold winters. Because Aedes aegypti require a warm climate, they typically do not live at altitudes above 1000 m, where the temperature is colder. These mosquitoes are associated with the living spaces of humans. They generally spend their entire lives in and around the houses where their eggs hatched.